Does anyone knows what this error means?

We are running AFP on OES2sp1 Linux10sp2 server. I noticed afp log file
showing "FPEnumerate returning ERROR (4FB7) at 5" from the begining to
the end. What does it mean?

Also some errors say:
afptcpd[12018]: [ERROR] Failed to open fork
afptcpd[12018]: From FPOpenFork

I have set up AFP and used it for three weeks. I found that afp service
was stopped every Monday morning. It seems it stopped Friday. The error
I saw from the log is shown above.

I would appreciate it very much if someone can give any advice.

Thanks a lot!